The White House said President Trump fired Rex Tillerson as State Department secretary now in order to get a new team in place before big negotiations with North Korea — but that timeline is already looking iffy.

Sen. Bob Corker, chairman of the Foreign Relations Committee, signaled he will schedule a confirmation hearing next month for Mike Pompeo, the man Mr. Trump picked to take over at state.

Given that the Senate is scheduled to be off for a two-week vacation surrounding Easter, that means the earliest the hearing could happen is the week of April 9 — or a month away. After his hearing, Mr. Pompeo would then have to clear a committee vote and a full floor vote.

Mr. Trump has said he would like to meet with Kim Jong Un by May, after the North Korean leader issued an invitation last week to talk through the growing tensions and his own nuclear ambitions.

A senior White House official said Tuesday that Mr. Trump made the changes now in order “to have his new team in place in advance of the upcoming talks with North Korea and various ongoing trade negotiations.”